Move slice dispatcher functionality to subtensor.py

pytensor/link/numba/dispatch/basic.py

-import operator
-import sys
 import warnings
 from copy import copy
 from functools import singledispatch
@@ -8,11 +6,10 @@ from textwrap import dedent
 import numba
 import numba.np.unsafe.ndarray as numba_ndarray
 import numpy as np
-from llvmlite import ir
 from numba import types
 from numba.core.errors import NumbaWarning, TypingError
 from numba.cpython.unsafe.tuple import tuple_setitem  # noqa: F401
-from numba.extending import box, overload
+from numba.extending import overload
 
 from pytensor import In, config
 from pytensor.compile import NUMBA
@@ -36,7 +33,7 @@ from pytensor.tensor.math import Dot
 from pytensor.tensor.shape import Reshape, Shape, Shape_i, SpecifyShape
 from pytensor.tensor.sort import ArgSortOp, SortOp
 from pytensor.tensor.type import TensorType
-from pytensor.tensor.type_other import MakeSlice, NoneConst
+from pytensor.tensor.type_other import NoneConst
 
 
 def numba_njit(*args, fastmath=None, **kwargs):
@@ -149,69 +146,6 @@ def create_numba_signature(
         return numba.types.void(*input_types)
 
 
-def slice_new(self, start, stop, step):
-    fnty = ir.FunctionType(self.pyobj, [self.pyobj, self.pyobj, self.pyobj])
-    fn = self._get_function(fnty, name="PySlice_New")
-    return self.builder.call(fn, [start, stop, step])
-
-
-def enable_slice_boxing():
-    """Enable boxing for Numba's native ``slice``s.
-
-    TODO: this can be removed when https://github.com/numba/numba/pull/6939 is
-    merged and a release is made.
-    """
-
-    @box(types.SliceType)
-    def box_slice(typ, val, c):
-        """Implement boxing for ``slice`` objects in Numba.
-
-        This makes it possible to return an Numba's internal representation of a
-        ``slice`` object as a proper ``slice`` to Python.
-        """
-        start = c.builder.extract_value(val, 0)
-        stop = c.builder.extract_value(val, 1)
-
-        none_val = ir.Constant(ir.IntType(64), sys.maxsize)
-
-        start_is_none = c.builder.icmp_signed("==", start, none_val)
-        start = c.builder.select(
-            start_is_none,
-            c.pyapi.get_null_object(),
-            c.box(types.int64, start),
-        )
-
-        stop_is_none = c.builder.icmp_signed("==", stop, none_val)
-        stop = c.builder.select(
-            stop_is_none,
-            c.pyapi.get_null_object(),
-            c.box(types.int64, stop),
-        )
-
-        if typ.has_step:
-            step = c.builder.extract_value(val, 2)
-            step_is_none = c.builder.icmp_signed("==", step, none_val)
-            step = c.builder.select(
-                step_is_none,
-                c.pyapi.get_null_object(),
-                c.box(types.int64, step),
-            )
-        else:
-            step = c.pyapi.get_null_object()
-
-        slice_val = slice_new(c.pyapi, start, stop, step)
-
-        return slice_val
-
-    @numba.extending.overload(operator.contains)
-    def in_seq_empty_tuple(x, y):
-        if isinstance(x, types.Tuple) and not x.types:
-            return lambda x, y: False
-
-
-enable_slice_boxing()
-
-
 def to_scalar(x):
     return np.asarray(x).item()
 
@@ -388,15 +322,6 @@ def numba_funcify_DeepCopyOp(op, node, **kwargs):
     return deepcopyop
 
 
-@numba_funcify.register(MakeSlice)
-def numba_funcify_MakeSlice(op, **kwargs):
-    @numba_njit
-    def makeslice(*x):
-        return slice(*x)
-
-    return makeslice
-
-
 @numba_funcify.register(Shape)
 def numba_funcify_Shape(op, **kwargs):
     @numba_njit

pytensor/link/numba/dispatch/subtensor.py

+import operator
+import sys
+
+import numba
 import numpy as np
+from llvmlite import ir
+from numba import types
+from numba.core.pythonapi import box
 
 from pytensor.graph import Type
 from pytensor.link.numba.dispatch import numba_funcify
@@ -14,7 +21,79 @@ from pytensor.tensor.subtensor import (
     IncSubtensor,
     Subtensor,
 )
-from pytensor.tensor.type_other import NoneTypeT, SliceType
+from pytensor.tensor.type_other import MakeSlice, NoneTypeT, SliceType
+
+
+def slice_new(self, start, stop, step):
+    fnty = ir.FunctionType(self.pyobj, [self.pyobj, self.pyobj, self.pyobj])
+    fn = self._get_function(fnty, name="PySlice_New")
+    return self.builder.call(fn, [start, stop, step])
+
+
+def enable_slice_boxing():
+    """Enable boxing for Numba's native ``slice``s.
+
+    TODO: this can be removed when https://github.com/numba/numba/pull/6939 is
+    merged and a release is made.
+    """
+
+    @box(types.SliceType)
+    def box_slice(typ, val, c):
+        """Implement boxing for ``slice`` objects in Numba.
+
+        This makes it possible to return an Numba's internal representation of a
+        ``slice`` object as a proper ``slice`` to Python.
+        """
+        start = c.builder.extract_value(val, 0)
+        stop = c.builder.extract_value(val, 1)
+
+        none_val = ir.Constant(ir.IntType(64), sys.maxsize)
+
+        start_is_none = c.builder.icmp_signed("==", start, none_val)
+        start = c.builder.select(
+            start_is_none,
+            c.pyapi.get_null_object(),
+            c.box(types.int64, start),
+        )
+
+        stop_is_none = c.builder.icmp_signed("==", stop, none_val)
+        stop = c.builder.select(
+            stop_is_none,
+            c.pyapi.get_null_object(),
+            c.box(types.int64, stop),
+        )
+
+        if typ.has_step:
+            step = c.builder.extract_value(val, 2)
+            step_is_none = c.builder.icmp_signed("==", step, none_val)
+            step = c.builder.select(
+                step_is_none,
+                c.pyapi.get_null_object(),
+                c.box(types.int64, step),
+            )
+        else:
+            step = c.pyapi.get_null_object()
+
+        slice_val = slice_new(c.pyapi, start, stop, step)
+
+        return slice_val
+
+    @numba.extending.overload(operator.contains)
+    def in_seq_empty_tuple(x, y):
+        if isinstance(x, types.Tuple) and not x.types:
+            return lambda x, y: False
+
+
+enable_slice_boxing()
+
+
+@numba_funcify.register(MakeSlice)
+def numba_funcify_MakeSlice(op, **kwargs):
+    @numba_njit
+    def makeslice(*x):
+        return slice(*x)
+
+    return makeslice
 
 
 @numba_funcify.register(Subtensor)